Spots come in varying sizes but almost always appear as black, and sometimes blue or red, creatures akin to typical monsters, albeit much stronger. They have the ability to possess humans, often killing them in the process and using their bodies as hosts. The Pope, Vincent Bridges, falls victim to this and manages to survive only to be killed by Rommy shortly thereafter. Rommy herself is a Spot using her body as a host. Described in her youth as a sweet girl, a Spot possess her, technically killing her, prior to the events of the story, which is the result of her sadistic personality. Her warped mind speaks of a planet, which is later revealed to be the Spot home world.
Spots originate from another planet. King Areulla VIII comes from this world, being a Spot himself, and accidentally hurled himself through space using strange, experimental magic. Seeking to return home, he began to work on a type of Precepts known as Life Magic that could get him back. However, this magic required for thousands of lives to be sacrificed to a mysterious stone known as the Pensient, so King Areulla set about thinking of a way to gather the required amount. Under the alias of a human traveler by the name of "Walls Garner", he deceived the leader of the Leymon people, Couber, into sacrificing Leymon lives to produce Pensients capable of generating enough energy to open a portal, hinted to be the Triverse Gate, to the Spot home world.
This ultimately failed to return King Areulla home, so he spent years figuring out a way to find a new person desperate enough, and bearing power, to deceive and enact the Precepts ritual again. His new victim became the Pope, who sought to resurrect his dead wife, Melissa Bridges, a woman of Leymon royalty. Over time, as more Pensients were created and gathered, King Areulla steadily increased his power by drawing from the energy of his home world via a portal in his castle atop Mount Ayre. Spots invaded Areulla, and even other countries, as a result. At the end of the story, the group defeats King Areulla and uses the power of Precepts to close the portal, thereafter eliminating the remaining Spots in the world.